Field of the Invention
The group of 1-functional allyl alcohol carboxylic esters encompasses economically important compounds which are either useful as such or can be reacted to form further economically important compounds, for example they can be saponified to form the corresponding 1-functional allyl alcohols.
It is known that 1-functional allyl alcohol carboxylic esters of the general formula 2 can be obtained according to the following scheme involving a 3,1-allyl rearrangement ##STR1## R.sup.1 and R.sup.3 =H, alkyl or aryl R.sup.2 =any radical, but not H
R.sup.4 =alkyl or aryl
by reacting 3-functional secondary or tertiary allyl alcohols of the general formula 1 with carboxylic anhydrides. The 3-functional allyl alcohols of the general formula 1 are in turn obtainable by addition of vinyl or acetylene metal compounds onto carbonyl compounds.
However, this rearrangement reaction in which an esterification of the rearranged alcohol function takes place simultaneously has hitherto proceeded in a quite unsatisfactory manner, particularly in respect of the yields achieved. In a typical example, it is carried out under strongly acidic conditions in a solvent mixture of acetic acid, acetic anhydride and p-toluenesulphonic acid, with the acetates of the rearranged allyl alcohols being obtained. However, this results in undesired secondary reactions such as eliminations or cyclizations which greatly reduce the yield of the desired rearranged product. Thus, when using, for example, linalool mainly cyclizations are observed, while the desired products geranyl acetate and neryl acetate are formed only as by-products.